There are numerous communication systems in operation today which utilize frequency modulation (FM). In current paging systems, for example, paging signals are transmitted from a paging transmitter to a multiplicity of portable paging receivers according to a pre-specified transmission protocol which includes, for example, serialized digitally coded synchronization, address, and message data words. The transmitters in current simulcast high data rate paging systems are spaced in order to minimize differential delay problems resulting from differences in time required for the paging signals to propagate from the transmitters. Specifically, the transmitter spacing distance is limited by differential delays associated with the reciprocal of the channel symbol rate. Differential delays between simulcast transmitters can cause severe problems when the differential delay between simulcast transmitters is larger than a fraction, usually in the neighborhood of 1/4 or 1/3 of the symbol time (Ts) for the channel rates. For example, Ts=1/2400 for a channel rates of 2400 BPS. Thus transmitters are usually spaced no further apart than some distance "X" which ensures that differential delays within the service area are smaller than 1/4 or 1/3 of Ts. This poses a problem where it is desired to send data at a significantly higher data rate. The restriction for the placement of transmitters also causes a high transmitter density requirement, which leads to higher costs due to an increased number of transmitters.
Thus, there is a need in the art for a messaging and paging system in which data can be sent at a higher speed than is available with currently feasible transmitter spacing. There is also a need in the art for a messaging and paging system with multiple-transmitters disposed to cover a geographic area where the coverage is based solely on signal strength and not on differential delay, thereby permitting lower transmitter density in a coverage area. There is a further need in the art for a messaging and paging system in which the simulcast characteristics of a high speed transmission can be chosen essentially independently of the channel data rate, up to the constraint of available bandwidth.